Boss Axle (No) Vent

[galaxy]

Well, I found this interesting. My new ‘12 Boss does not have an axle vent. At all. The hole is plugged. That’s not normal, right??? The hole is there, but there’s a bolt/plug in it.

I noticed this because when I went to pull the fill plug and check the oil, it let air out. It was clearly pressurized.

Thoughts???

 

[galaxy]

This in the hole…

 

[galaxy]

It looks/feels factory. And it’s a brand new car, so I have no reason to suspect someone did this due to leaks.

 

[BackInBlack]

It's correct. In Boss cars the vent is on the top of the diff cover. It makes seepage a little less likely. The stock GT diff cover doesn't have this feature so on those cars it's on the axle.

 

[galaxy]

Aaahhhhh. sh*t, I found it.

So is that normal then for the thing to hold pressure? She’s been sitting for a few days also, thus it caught me by surprise to hear it vent when I pulled the plug.

 

[BackInBlack]

Aaahhhhh. sh*t, I found it.

So is that normal then for the thing to hold pressure? She’s been sitting for a few days also, thus it caught me by surprise to hear it vent when I pulled the plug.

Not sure about that part. I've never experienced that myself. It could be your vent is dirty/clogged? Super cheap part so might be worth replacing as a just in case thing. Then again, it'd probably clean up easily enough if it is clogged.

I think this is the one:

https://lmr.com/item/LRS-4022A/86-04-Mustang-88-Rear-Axle-Housing-Vent

 

[Champale]

If you ever plan on driving at high speeds (over 100mph), you will want a rear axle overflow catch can. JLT used to make a great one that a lot of us used 10+ years ago that was a simple catch can with a single bolt mounted bracket but I don't see one online now. Any of the short vent style ones will allow the differential fluid flow out all over your diff when you do high speeds. After a quick google, it looks like Kohr and Cortex sell fancy ones.

https://kohrmotorsports.com/product/axle-differential-vent-kit-mustang-universal-club/

https://www.cortexracing.com/shop/rab-40-1000-cortex-differential-breather-vent-catch-tank-kit-universal-1703?attribute_values=2,8,7

EDIT: This: https://jonsespeedlab.com/products/jlt-performance-rear-axle-expansion-tank-2005-14-mustang-jlt-ax05